#include <stdio.h>

void revese(char* p)
{
	char  *left = p;
	char  *right = p+strlen(p)-1;
	while (left<right)
	{
		char tmp = *left;
		*left = *right;
		*right = tmp;
		++left;
		--right;
	}

}

int main()
{
	char str[] = { "i am a student!" };
	printf("%s\n", str);
	revese(str);
	printf("%s\n", str);

}